Having bought hundreds (literally) of Dell/Lenovo/HP business class laptops - I've never had a swollen battery. I've had some batteries prematurely die and have had them replaced (Dell will even put a 3 year warranty on the battery for a small fee) - but no swelling.

It's kind of ridiculous that they never bothered to fix that or the underpowered charger issue. The batteries still have issues. While recent models lack user serviceable batteries, the older parts are still sold. They're mostly rated at 1.5-2 stars on Apple's site. If anyone doubts that the batteries are absolute garbage, I link them to that.